I've been using the 16T freewheel for MTB singlespeed duties twice a week for 4 months and still going strong. No problems with engagement, nice and quiet, cheap - what more do you want? No need for WI at the moment!
Lasted about a year before the prawls finally decided to pack up, did skip quite a bit before it finally gave up the ghost so I reckon I had about 10 months of totally smooth and silent running - which is not too bad for the price. I bought two and have kept one as a spare - just need to buy the tool to get the thing off now though, doh :(
I would recommend this product, I have owned this product for about a week now. I have seen some more negative reviews on this product and yes i do agree that this will probabally not last that long but hey, its good for the price :)